A brake shoe is typically biased against a backing plate by a spring compressed between a web of the backing plate and a retainer cap which has its travel limited relative to the backing plate by a nail with its head disposed outside the backing plate and a flat barb-like tip on the opposite end engaging the retainer cap. The barb-like tip passes through an opening of complementary shape in the cap with the cap being twisted approximately 90 degrees relative to the flange to produce engagement between the nail and the cap. It is desirable to eliminate the need for this twisting motion. The present invention provides a nail and cap combination which can be assembled without any twisting motion.